A toner cartridge comprises a toner cartridge main body which houses
toner, a discharging opening which supplies the toner housed in the toner
cartridge main body to an image forming apparatus, a shutter which opens
the discharging opening when the toner cartridge main body is inserted in
the image forming apparatus and closes the discharging opening when the
toner cartridge main body is removed from the image forming apparatus,
and a notifying member which includes a first protrusion provided in the
toner cartridge main body, to show that the toner cartridge main body is
set in the image forming apparatus by temporary engaging with a second
protrusion provided in the image forming apparatus at the same time when
the shutter completes the opening of the discharging opening, when the
toner cartridge main body is inserted in the image forming apparatus.